Production of sulfonium salts of carboxylic acids or sulfonic acids



United States Patent 3,538,132 PRODUCTION OF SULFONIUM SALTS 0F CAR-BOXYLIC ACIDS 0R SULFONIC ACIDS Harry Distler, Ludwigshafen (Rhine),Germany, assignor to Badisch Anilin- & Soda-Fabrik Aktiengesellschaft,Ludwigshafen (Rhine), Germany No Drawing. Filed Dec. 7, 1967, Ser. No.688.696 Claims priority, application Germany, Dec. 13, 1966, 1,267,216;Apr. 28, 1967, 1,618,147 Int. Cl. C08h 9/02 US. Cl. 260399 11 ClaimsABSTRACT OF THE DISCLOSURE Production of sulfonium salts of carboxylicacids or sulfom'c acids by reaction of thioethers having aliphatic,cycloaliphatic, araliphatic or aromatic radicals having up to twentycarbon atoms with alkylene oxides having two to four carbon atoms andcarboxylic acids having one to twenty carbon atoms or organic sulfonicacids having an aliphatic, cycloaliphatic, araliphatic or aromaticradical having up to twenty carbon atoms, in about equivalent amounts,the reaction being carried out at temperatures of from to 80 C. withoutusing water. Sulfonium salts of carboxylic acids or sulfionic acids maybe used as bactericides or textile assistants.

This invention relates to an improved process for the production ofsulfonium salts of carboxylic or sulfonic acids from thioethers,alkylene oxides and carboxylic or sulfonic acids.

It is known from German printed application No. 1,224,498 that sulfoniumsalts of carboxylic acids are obtained when a solution oftrialkylsulfonium sulfate is allowed to flow over a basic ion exchangerand the sulfonium hydroxide formed is neutralized with a carboxylicacid. This method is very expensive because it uses basic ionexchangers.

According to another method which is described in US. patentspecification No. 3,159,682, sulfonium salts of carboxylic acids areobtained by reaction of thioethers with alkylene oxides and aqueouscarboxylic acids. The process however gives yields of only 85% of thetheory. The sulfonium salts prepared are very difiicult to purify sothat the quality in many cases does not satisfy the required standard.This is true particularly when the carboxylic acids used as startingmaterials are not soluble in water.

It is an object of this invention to provide an improved process formanufacturing sulfonium salts of carboxylic or sulfonic acids in asimple manner and in practically quantitative yields. Another object ofthis invention is to provide an improved process by which sulfoniumsalts of carboxylic acids or sulfonic acids are immediately obtained ingreat purity.

In accordance with this invention, these and other objects andadvantages are obtained in an improved process for the production ofsulfonium salts of carboxylic or sulfonic acids by the reaction ofthioethers which have aliphatic, cycloaliphatic, araliphatic or aromaticradicals having up to twenty carbon atoms, with alkylene oxides havingtwo to four carbon atoms and carboxylic acids having one to twentycarbon atoms or organic sulfonic acids which have aliphatic,cycloaliphatic, araliphatic or aromatic radicals having up to twentycarbon atoms, in about equivalent amounts, the improvement consisting incarrying out the reaction at temperatures of 20 to 80 C. without usingwater.

We have now found that sulfonium salts of carboxylic or sulfonic acidsare advantageously obtained by reaction of thioethers with alkyleneoxides and carboxylic or sul- "ice fonic acids by carrying out thereaction at 20 to C. without using Water.

The new process has the advantage that sulfonium salts of carboxylic orsulfonic acids are immediately obtained in geat purity in a simple wayin practically quantitative yie s.

The new process is remarkable because it is stated in U.S. patentspecification 3,159,682 that the process proceeds with adequate yieldsonly in the presence of water, preferably at temperatures of from 0 to20 C. Furthermore it is necessary to overcome a prejudice to carry outthe reaction at temperatures of more than 50 C. because in Britishpatent specification No. 1,058,075 it is stated thathydroxyalkylcarb'oxylic esters are formed in the reaction of carboxylicacids with epoxides in the presence of sulfonium salts and/0rthioethers.

It is preferred to use for the reaction carboxylic acids having 1 to 20carbon atoms such as acetic acid, propi- -on1c acid, caproic acid,lauric acid, stearic acid, oleic acid, adipic acid, palmitic acid,polyacrylic acid, citric acid, maleic acid, oxalic acid, phthalic acid,terephthalic acid and trifiuoroacetic acid.

Preferred sulfonic acids are organic sulfonic acids which have analiphatic, cycloaliphatic, araliphatic or aromatic radical having up totwenty, particularly up to elghteen, carbon atoms. They may contain thesulfonic acid group one or more times, for example one to four times, inthe molecule. Moreover they may be unsaturated, for example may containone or two olefinic double bonds or substituents which are inert underthe reaction conditions, such as halogen atoms or alkoxy groups havingone to four carbon atoms. It is however also possible to use for thereaction, compounds which contain more than four sulfonic acid groups inthe molecule, for example polyvinylsulfonic acid. Monosulfonic acidscontaining an alkyl radical, aralkyl radical or aryl radical having upto eighteen carbon atoms are preferred particularly. EX- amples ofsuitable sulfonic acids are: methylsulfonic acid, butylsulfonic acid,octylsulfonic acid, dodecylsulfonic acid, tridecylsulfonic acid,cyclohexylsulfonic acid, cyclooctylsulfonic acid, benzylsulfonic acid,dodecylbenzenesulfonic acid, benzenesulfonic acid,naphthalene-Z-sulfonic acid, naphthalene-l-sulfonic acid,-benzene-1,3-disulfonic acid, naphthalene-1,5-disulfonic acid orpolyvinylsulfonic acid. Long chain aliphatic or araliphatic sulfonicacids havmg twelve to eighteen carbon atoms, which contain one sulfonicacid group in the molecule and which, apart from the sulfonic acidgroups have hydrocarbon structure have special importance.

Thioether, alkylene oxide and carboxylic acid or sulfomc acid areadvantageously reacted in equivalent amounts. Slight deviations from theequivalent amounts are possible. When using dicarboxylic acids,polycarboxylic acids or polysulfonic acids it is possible to react onlypart of the carboxyl or sulfonic acid groups.

The reaction proceeds at temperatures of from 20 to 80 C. Particularlygood results are achieved at temperatures of 30 to 60 C. When startingmaterials which are gaseous at room temperature are used in the liquidphase, or temperatures are used which are above the boiling point of thestarting materials, the reaction may be carried out at superatmosphericpressure, for example at up to 30 atmospheres.

It is an essential feature of the invention that the reaction is carriedout without using water; this does not mean that absolutely no water maybe present in the reaction mixture. Small amounts of water, for example1 to 2% by weight, which are often contained in the starting materialsdo not affect the reaction.

The process according to the invention may be carried out for example byplacing thioether and carboxylic or sulfonic acid in a stirred vesseland adding the specified amount of an alkylene oxide at the specifiedtemperature. When gaseous ethylene oxide is used as the startingmaterial, it may be passed in as a gas at atmospheric pressure or it maybe. metered in under pressure as a liquid. The reaction is in generalover after three to fortyeight hours. The melt obtained need not befurther purified, because the reaction proceeds almost quantitatively.

Sulfonium salts of carboxylic acids or of sulfonic acids which areprepared by the process according to this invention are suitable asbactericides and as textile assistants (cf. US. patent specification No.3,159,682).

The invention is illustrated by the following examples in which theparts mentioned are parts by weight.

EXAMPLE 1 A mixture of 200 parts of lauric acid and 125 parts oftechnical grade thiodiglycol (98%) is heated to 44 C. in a stirredvessel. Then 50 parts of ethylene oxide is passed in during the courseof fifteen hours at 40 C. and the whole is allowed to cool. 370 parts oftris-(phydroxyethyl)-sulfonium laurate is obtained having a meltingpoint of 101 to 105 C.

Analysis.-Calcd for (percent): C H O S (molecular weight 366) C, 59; H,10.38; 0, 21.84; S, 8.74. Found (percent): C, 59.3; H, 10.5; 0, 21.7; S,8.3.

EXAMPLE 2 parts of ethylene oxide is passed in the course of fifteenhours at 60 C. into a melt of 128 parts of palmitic acid and 62.5 partsof technical grade thiodiglycol (98%) in the manner described inExample 1. After the melt has cooled, 213 parts of tris-(B-hydroxyethyD-sulfonium palmitate is obtained which has good solubility in water and amelting point of 94 to 96 C. The yield is 100% of the theory.

EXAMPLE 3 In a manner analogous to that in Example 1, 282 parts of oleicacid, 125 parts of technical grade thiodiglycol (98%) and 50 parts ofethylene oxide are reacted at C. 426 parts oftris-(fl-hydroxyethyl)-sulfonium oleate is obtained. The yield is 100%of the theory.

EXAMPLE 4 In a manner analogous to that described in Example 1, 286parts of stearic acid and 125 parts of technical grade thiodiglycol(98%) are reacted with 50 parts of ethylene oxide at 60 C. in the courseof fifteen hours. 430 parts of tris-(B-hydroxyethyl)-soulfonium stearateis obtained having a melting point of 85 C. The yield is 100% of thetheory.

EXAMPLE 5 83 parts of terephthalic acid and 125 parts of technical gradethiodiglycol (98%) are reacted with 50 parts of ethylene oxide at 30 toC. as described in Example 1. The reaction is over after forty-eighthours. 249 parts of (tris-(B-hydroxyethyl)-sulfonium terephthalate isobtained as a colorless melt which crystallizes after some time. Afterrecrystallization from alcohol, colorless crystals having a meltingpoint of 107 to 110 C. are obtained. The yield is 100% of the theory.

EXAMPLE 6 58 parts of maleic acid and 125 parts of technical gradethiodiglycol (98%) are reacted with parts of ethylene oxide in a manneranalogous to that described in Examp e 1. The reaction is over afterfive to six hours. 230 parts of bis-(tris-(fl-hydroxyethyl)-sullfonium)maleateis obtained as a colorless viscous melt having the refractiveindex n -=1.5208.

EXAMPLE 7 parts of acetic acid and 125 parts of technical gradethiodiglycol (98%) are reacted with 50 parts of ethylene 4 oxide in amanner analogous to that in Example 1. A colorless viscous liquid isobtained having the refractive index n =1.5052 which crystallizes uponprolonged standing. The tris-(fi-hydroxyethyl)-sulfonium acetate isstrongly hygroscopic and melts at 102 to 104 C. The yield is 100% of thetheory.

EXAMPLE 8 A mixture of 128 parts of palmitic acid and 62 parts ofthiodiglycol is heated at 65 C. in a stirred vessel. 46 parts ofepichlorohydrin is added in the course of two hours. 236 parts ofbis-(,B-hydroxyethyl)-2-hydroxy-3- chloropropylsulfoni-um palmitate of awaxy consistency is obtained which melts at 91 C. after it has beenrecrystallized from acetone.

EXAMPLE 9 100 parts of lauric acid is reacted in a stirred vessel with61 parts of thiodiglycol and 46 parts of epichlorohydrin at 42 C. 207parts of bis-(,B-hydroxyethyD-2- hydroxy-3-chloropropylsulfonium laurateis obtained having a melting point of 57 to 58 C.

EXAMPLE 10 568 parts of stearic acid and 244 parts of thiodiglycol areheated to 70 to C. in a reactor and then reacted with 184 parts ofepichlorohydrin. 996 parts of bis- (fl-hydroxyethyD-2 hydroxy-3chloropropylsulfonium stearate having a melting point of 62 to 63 C. isobtained.

EXAMPLE 11 142 parts of oleic acid and 61 parts of thiodiglycol areheated to 40 to 50 C. in a stirred vessel and then reacted with 46 partsof epichlorohydrin. After reaction has continued for another three hours50 C., 249 parts of bis-(fl-hydroxyethyl)-2-hydroxy-3chloropropylsulfonium oleate is obtained as a viscous yellow oil.

EXAMPLE 12 132 parts of benzoic acid and 122 parts of thiodiglycol areplaced in a reactor. The mixture is heated to 60 C. and then reactedwith 92.5 parts of epichlorohydrin. 346 parts ofbis-(,B-hydroxyethyl)-2-hydroxy-3-chloropropylsulfoni-um benzoate isobtained as a viscous liquid.

EXAMPLE 13 187 parts of thiodiglycol is placed in a stirred vessel and380 parts of 86% by weight dodecylbenzenesulfonic acid is introduced and60 parts of ethylene oxide is passed in as a gas at the same time in thecourse of two to three hours at 20 to 40 C. The reaction is allowed tocontinue for another three hours at room temperature. 627 parts of ahighly viscous syrup is obtained which dissolves in Water to give aclear neutral solution. The syrup obtained has a refractive index n=1.5172 and the content of tris-(fl-hydroxyethyl)-sulf0niumdodecylbenzenesulfonate is about by weight. This content is determincdby ascertaining the sulfur content after the sulfate ions have beenremoved with barium hydroxide.

EXAMPLE 14 parts of 98% thiodiglycol is placed in a stirred vessel andat 20 to 40 C. in the course of two hours 172 parts of p-toluenesulfonicacid is introduced and 46 parts of ethylene oxide gas passed insimultaneously. The reaction is then allowed to continue for anothertwelve hours at 30 to 40 C. 343 parts (about 99% of the theory) oftris-(B-hydroxyethyl)-sulfonium ptoluenesulfonate is obtained as aviscous syrup which dissolves in water to give a clear solution and hasa. refractive index n =1.5375.

I claim:

1. An improved process for the production of sulfonium salts ofcarboxylic acids or sulfonic acids by reaction of thioethers which havealiphatic, cycloaliphatic, araliphatic or aromatic radicals having up totwenty carbon atoms with alkylene oxides having two to four. carbonatoms and carboxylic acids having one to twenty carbon atoms or organicsulfonic acids which have an aliphatic,

cycloaliphatic, araliphatic or aromatic radical having up to twentycarbon atoms in about equivalent amounts, wherein the improvementconsists in carrying out the reaction at temperatures of from 20 to 80C. in the presence in the reaction mixture of not more than 2% by weightof water.

2. A process as claimed in claim 1 in which a thioether is used whichhas an alkyl radical having one to twenty carbon atoms.

3. A process as claimed in claim 1 in which bis-(,6-hydroxyethyl)thioether is used.

4. A process as claimed in claim 1 in which bis-(,8-hydroxypropyl)thioether is used.

5. A process as claimed in claim 1 in which ethylene oxide is used asthe alkylene oxide.

6. A process as claimed in claim 1 in which propylene oxide is used asthe alkylene oxide.

7. A process as claimed in claim 1 in which an aliphatic monocarboxylicacid is used which has one to eighteen carbon atoms.

8. A process as claimed in claim 1 in which an aliphatic sulfonic acidhaving twelve to eighteen carbon atoms is used.

9. A process as claimed in claim 1 in which an araliphatic sulfonic acidhaving twelve to eighteen carbon atoms is used.

10. A process as claimed in claim 1 carried out at a temperature of fromto C.

11. A process as claimed in claim 1 carried out at superatmosphericpressure up to 30 atmospheres.

References Cited UNITED STATES PATENTS 3,159,682 12/1964 Baird et al260-607 ELBERT L. ROBERTS, Primary Examiner US. Cl. X.R.

